+# Example showing how to create a disk image.
+
+require 'guestfs'
+
+output = "disk.img"
+
+g = Guestfs::Guestfs.new()
+
+# Create a raw-format sparse disk image, 512 MB in size.
+File.open(output, "w") {
+ |f| f.truncate(512 * 1024 * 1024)
+}
+
+# Set the trace flag so that we can see each libguestfs call.
+g.set_trace(1)
+
+# Set the autosync flag so that the disk will be synchronized
+# automatically when the libguestfs handle is closed.
+g.set_autosync(1)
+
+# Attach the disk image to libguestfs.
+g.add_drive_opts(output, :format => "raw")
+
+# Run the libguestfs back-end.
+g.launch();
+
+# Get the list of devices. Because we only added one drive
+# above, we expect that this list should contain a single
+# element.
+devices = g.list_devices()
+if devices.length != 1 then
+ raise "error: expected a single device from list-devices"
+end
+
+# Partition the disk as one single MBR partition.
+g.part_disk(devices[0], "mbr")
+
+# Get the list of partitions. We expect a single element, which
+# is the partition we have just created.
+partitions = g.list_partitions()
+if partitions.length != 1 then
+ raise "error: expected a single partition from list-partitions"
+end
+
+# Create a filesystem on the partition.
+g.mkfs("ext4", partitions[0])
+
+# Now mount the filesystem so that we can add files.
+g.mount_options("", partitions[0], "/")
+
+# Create some files and directories.
+g.touch("/empty")
+message = "Hello, world\n"
+g.write("/hello", message)
+g.mkdir("/foo")
+
+# This one uploads the local file /etc/resolv.conf into
+# the disk image.
+g.upload("/etc/resolv.conf", "/foo/resolv.conf")
+
+# Because 'autosync' was set (above) we can just close the handle
+# and the disk contents will be synchronized. You can also do
+# this manually by calling g#umount_all and g#sync.
+g.close()